Re: 27.0.50: How can I test a buffer-local window-configuration-change-hook in batch mode?

[Eli Zaretskii]

> From: Stefan Monnier <address@hidden>
> Cc: Phil Sainty <address@hidden>,  address@hidden,  address@hidden
> Date: Sat, 26 Oct 2019 08:11:21 -0400
> 
> >> I don't think long lines pose any performance problems in buffers
> >> which are never displayed
> >
> > You are wrong: it will cause problems in any function that uses the
> > display code, even if nothing is displayed.  For example,
> > vertical-motion, next-line, posn-at-point, etc. all use the display
> > code internally.
> 
> In theory you're right.  But I think in practice "buffers that aren't
> displayed" is a pretty good approximation of "so-long won't help".

I don't understand how practice makes theory unimportant in this case.
There's a leap in your logic that I couldn't follow.

> >> I've not been able to spot any down-sides to the change, so I'm pretty
> >> sure it's the right thing to do.
> > Well, one downside is that you now need to use a hook that was not
> > really meant for that, or we'd need to introduce yet another hook.
> 
> I missed something: which new hook would be needed?

This sub-thread was in response to Martin's question here:

  https://lists.gnu.org/archive/html/emacs-devel/2019-10/msg01013.html